And well, being an alternate version of Jarren, Ren had to have a taur form XD

Only that since he being Terragen was artificially made by Darkmoon by growing his tissue on a synthetic skeleton of his quadruped body prior to the modifications, creating a whole secondary half as an extension of his body for him and Skytten in order to replicate the physical capabilities and advantages seen in the Garlesh.

Ren, living on a ruined world and having acquired consciousness until after the great devastation caused by the artificial intelligence Abraxas, knew little of what he was or what other capabilities he had, but after a scan of one of Darkmoon's old facilities he discovered that for some reason his radar identified a bioacoustic signal and vital signs identical to his own deep within, and at first thinking that it could be another complete and still active Terragen, he managed to go inside the place, discovering that it was really an extension of his body left behind by his creators long ago and that it was still in perfect condition having been preserved in a cryo chamber.

Somewhat confused but with the curiosity that characterizes him, Ren discovered that where the missing hind legs of the quadruped torso were placed he could place his legs and these were reconfigured to have the shape of hind legs and likewise with his tail by connecting it where he should have it in quadruped torso, with what after finishing connecting his upper half with the lower half he tested what his alternate versions feel every day when walking and moving with four legs, leaving a good optional feature to wear from time to time with which he has greater resistance and speed, besides that in his opinion with this form he is more connected to his original species and to nature.